Popt is a C library for parsing command line parameters. Popt was
heavily influenced by the getopt() and getopt_long() functions, but it
improves on them by allowing more powerful argument expansion. Popt
can parse arbitrary argv[] style arrays and automatically set
variables based on command line arguments. Popt allows command line
arguments to be aliased via configuration files and includes utility
functions for parsing arbitrary strings into argv[] arrays using
shell-like rules.